https://www.acmicpc.net/problem/3036

링.java

import java.math.BigInteger;
import java.util.*;

public class Main {
	public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        BigInteger firstRing = new BigInteger(sc.next()); // 첫 번째 링
        BigInteger[] num = new BigInteger[N-1];
        for (int i=0; i<N-1; i++) // 나머지 링
            num[i] = new BigInteger(sc.next());
        sc.close();

        for (BigInteger bi : num) {
            BigInteger gcd = firstRing.gcd(bi);
            System.out.println(firstRing.divide(gcd)+"/"+bi.divide(gcd));
        }
	}
}